Qualifications
It doesn't take years of postgraduate education to become a casino dealer—but you can't just phone it in, either. There's a skill set you need to have in order for a casino to consider you and it involves a combination of personality, quick-thinking, and gaming experience.
If you're the right fit but you're a little green behind the ears, you'll have to undergo an extensive training program—sometimes at an off-site gaming school—in which you'll be instructed on a variety of games (source). You won't be allowed on to the floor until you can show that you've mastered the games, along with the abilities to quickly count out and deliver change, handle money, and work with the card machines.
Dealers who want to grow to be supervisors or even gaming managers will need another level of training and experience. Years in the business will help build trust with your casino higher-ups, but getting a business education will make them confident that you can handle the larger responsibilities of management.
You might also be involved in hiring and firing, in which case you really need to be a people person—faking it like you do on the casino floor won't cut it with human resources.